Known Exploited Vulnerability
8.8
HIGH CVSS 3.1
CVE-2021-26828
OpenPLC ScadaBR Unrestricted Upload of File with Dangerous Type Vulnerability - [Actively Exploited]
Description

OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows remote authenticated users to upload and execute arbitrary JSP files via view_edit.shtm.

INFO

Published Date :

June 11, 2021, 12:15 p.m.

Last Modified :

Dec. 4, 2025, 2:47 p.m.

Remotely Exploit :

Yes !
CISA Notification
CISA KEV (Known Exploited Vulnerabilities)

For the benefit of the cybersecurity community and network defenders—and to help every organization better manage vulnerabilities and keep pace with threat activity—CISA maintains the authoritative source of vulnerabilities that have been exploited in the wild.

Description :

OpenPLC ScadaBR contains an unrestricted upload of file with dangerous type vulnerability that allows remote authenticated users to upload and execute arbitrary JSP files via view_edit.shtm.

Required Action :

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Notes :

This vulnerability could affect an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: https://github.com/SCADA-LTS/Scada-LTS/pull/2174 ; https://nvd.nist.gov/vuln/detail/CVE-2021-26828

Affected Products

The following products are affected by CVE-2021-26828 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
1 Microsoft windows
1 Scadabr scadabr
1 Openplcproject scadabr
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 MEDIUM [email protected]
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH 134c704f-9b21-4f2e-91b3-4a467353bcc0
Public PoC/Exploit Available at Github

CVE-2021-26828 has a 15 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-26828.

URL Resource
http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 Exploit Vendor Advisory Broken Link
http://packetstormsecurity.com/files/162564/ScadaBR-1.0-1.1CE-Linux-Shell-Upload.html Exploit Third Party Advisory
https://youtu.be/k1teIStQr1A Exploit Third Party Advisory
http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 Exploit Vendor Advisory Broken Link
http://packetstormsecurity.com/files/162564/ScadaBR-1.0-1.1CE-Linux-Shell-Upload.html Exploit Third Party Advisory
https://youtu.be/k1teIStQr1A Exploit Third Party Advisory
https://github.com/SCADA-LTS/Scada-LTS/pull/2174 Issue Tracking Patch
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26828 US Government Resource
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-26828 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-26828 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

All-in-one ICS/SCADA hacking, red teaming, malware analysis, detection, and lab architecture cheat sheet

cheatsheet detection-engineering exploitation hacking ics ics-security industrial-cybersecurity malware-simulation mitre-attack ot playbook scada scada-security security-tools stuxnet triton ladder-logic-analysis plc-hacking critical-infrastructure-protection ot-security

Python Zeek

Updated: 1 week, 6 days ago
1 stars 0 fork 0 watcher
Born at : Nov. 29, 2025, 3:40 a.m. This repo has been linked 3 different CVEs too.

None

Updated: 5 months, 1 week ago
1 stars 0 fork 0 watcher
Born at : July 3, 2025, 1:39 a.m. This repo has been linked 1 different CVEs too.

None

Python

Updated: 6 months ago
0 stars 0 fork 0 watcher
Born at : June 14, 2025, 9:56 a.m. This repo has been linked 1 different CVEs too.

ScadaFlare Authenticated RCE Exploit Framework for ScadaBR (CVE-2021-26828) OpenPLC ScadaBR

alchemy ctf exploit htb ics redteam reverse-shell scada scadabr cve-2021-26828 exploitation htb-scripts ics-security scada-security

Python

Updated: 1 week, 6 days ago
2 stars 0 fork 0 watcher
Born at : May 30, 2025, 12:59 a.m. This repo has been linked 1 different CVEs too.

None

HTML Python Shell

Updated: 5 months, 1 week ago
0 stars 0 fork 0 watcher
Born at : Feb. 13, 2025, 8:50 a.m. This repo has been linked 891 different CVEs too.

A client for gathering vulnerability-related information from GitHub Gists.

Python Dockerfile

Updated: 3 months, 3 weeks ago
1 stars 0 fork 0 watcher
Born at : Jan. 6, 2025, 10:33 p.m. This repo has been linked 1 different CVEs too.

All CVE - PoC in GitHub

poc proofofconcept tester allcve cvegithub cvenew cvepoc cveupdate

Updated: 6 months, 1 week ago
12 stars 3 fork 3 watcher
Born at : March 22, 2024, 3:58 p.m. This repo has been linked 931 different CVEs too.

None

Updated: 5 months, 3 weeks ago
2 stars 0 fork 0 watcher
Born at : March 11, 2024, 1:21 p.m. This repo has been linked 935 different CVEs too.

None

Dockerfile Shell Python HTML Roff CSS Smalltalk C++ MATLAB

Updated: 1 year ago
0 stars 0 fork 0 watcher
Born at : Dec. 18, 2023, 10:26 a.m. This repo has been linked 1 different CVEs too.

None

Python

Updated: 2 years ago
0 stars 0 fork 0 watcher
Born at : Dec. 8, 2023, 9:37 p.m. This repo has been linked 1 different CVEs too.

None

Updated: 2 years, 8 months ago
0 stars 2 fork 2 watcher
Born at : April 8, 2023, 6:19 a.m. This repo has been linked 928 different CVEs too.

None

Updated: 1 year, 10 months ago
20 stars 3 fork 3 watcher
Born at : Feb. 14, 2023, 6:10 p.m. This repo has been linked 921 different CVEs too.

None

Updated: 6 months, 3 weeks ago
2 stars 2 fork 2 watcher
Born at : Nov. 25, 2022, 5:43 p.m. This repo has been linked 935 different CVEs too.

None

Updated: 8 months, 2 weeks ago
9 stars 1 fork 1 watcher
Born at : June 21, 2022, 7:45 a.m. This repo has been linked 944 different CVEs too.

None

Python

Updated: 5 months, 2 weeks ago
8 stars 3 fork 3 watcher
Born at : March 31, 2021, 2:39 a.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-26828 vulnerability anywhere in the article.

  • CybersecurityNews
CISA Warns of OpenPLC ScadaBR File Upload Vulnerability Exploited in Attacks

Critical vulnerability has been added to CISA’s Known Exploited Vulnerabilities list, warning organizations about a dangerous file-upload flaw in OpenPLC ScadaBR systems. The vulnerability allows remo ... Read more

Published Date: Dec 04, 2025 (1 week, 4 days ago)
  • Daily CyberSecurity
Pro-Russian Hacktivist Group TwoNet Exposed for Fabricating Critical Infrastructure Attacks to Boost Reputation

Forescout Research has uncovered a disturbing new tactic among pro-Russian hacktivists — fabricating real-world critical infrastructure attacks to inflate their reputation. In a recent case, a newly f ... Read more

Published Date: Oct 13, 2025 (2 months ago)

The following table lists the changes that have been made to the CVE-2021-26828 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Modified Analysis by [email protected]

    Dec. 04, 2025

    Action Type Old Value New Value
    Added CPE Configuration AND OR *cpe:2.3:a:scadabr:scadabr:*:*:*:*:*:*:*:* versions up to (including) 0.9.1 OR cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:a:scadabr:scadabr:*:*:*:*:*:*:*:* versions up to (including) 1.12.4 OR cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*
    Removed CPE Configuration OR *cpe:2.3:a:openplcproject:scadabr:*:*:*:*:*:linux:*:* versions up to (including) 0.9.1 *cpe:2.3:a:openplcproject:scadabr:*:*:*:*:*:windows:*:* versions up to (including) 1.12.4
    Changed Reference Type MITRE: http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 Types: Exploit, Vendor Advisory MITRE: http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 Types: Broken Link, Exploit, Vendor Advisory
    Added Reference Type CISA-ADP: https://github.com/SCADA-LTS/Scada-LTS/pull/2174 Types: Issue Tracking, Patch
    Added Reference Type CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26828 Types: US Government Resource
    Changed Reference Type CVE: http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 Types: Exploit, Vendor Advisory CVE: http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 Types: Broken Link, Exploit, Vendor Advisory
  • CVE CISA KEV Update by 9119a7d8-5eab-497f-8521-727c672e3725

    Dec. 04, 2025

    Action Type Old Value New Value
    Added Date Added 2025-12-03
    Added Due Date 2025-12-24
    Added Required Action Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
    Added Vulnerability Name OpenPLC ScadaBR Unrestricted Upload of File with Dangerous Type Vulnerability
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Dec. 03, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-434
    Added Reference https://github.com/SCADA-LTS/Scada-LTS/pull/2174
    Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26828
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4
    Added Reference http://packetstormsecurity.com/files/162564/ScadaBR-1.0-1.1CE-Linux-Shell-Upload.html
    Added Reference https://youtu.be/k1teIStQr1A
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Jun. 21, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:S/C:P/I:P/A:P)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 No Types Assigned http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 Exploit, Vendor Advisory
    Changed Reference Type http://packetstormsecurity.com/files/162564/ScadaBR-1.0-1.1CE-Linux-Shell-Upload.html No Types Assigned http://packetstormsecurity.com/files/162564/ScadaBR-1.0-1.1CE-Linux-Shell-Upload.html Exploit, Third Party Advisory
    Changed Reference Type https://youtu.be/k1teIStQr1A No Types Assigned https://youtu.be/k1teIStQr1A Exploit, Third Party Advisory
    Added CWE NIST CWE-434
    Added CPE Configuration OR *cpe:2.3:a:openplcproject:scadabr:*:*:*:*:*:linux:*:* versions up to (including) 0.9.1 *cpe:2.3:a:openplcproject:scadabr:*:*:*:*:*:windows:*:* versions up to (including) 1.12.4
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 8.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 6.5
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

80.12 }} -1.43%

score

0.99066

percentile